1. A Review of General Chemistry

For each compound, state whether its bonding is covalent, ionic, or a mixture of covalent and ionic.

a. NaCl

b. NaOH

c. CH₃Li

d. CH₂Cl₂

e. NaOCH₃

f. HCO₂Na

g. CF₄

Use electronegativities to predict the direction of the dipole moments of the following bonds.

(f) N—Cl

(g) N—O

(h) N—S

(i) N—B

(j) B—Cl

Use the symbols δ⁺ and δ⁻ to show the direction of the polarity of the indicated bond in each of the following compounds:

g. I—Cl

h. H₂N—OH

Use the symbols δ⁺ and δ⁻ to show the direction of the polarity of the indicated bond in each of the following compounds:

c. H₃C—NH₂

d. H₃C—Cl

There are three isomers with molecular formula C₂H₂Cl₂. Draw their structures. Which one does not have a dipole moment?

Explain why CH₃Cl has a greater dipole moment than CH₃F even though F is more electronegative than Cl.

Which of the following molecules would you expect to have a dipole moment of zero?

a. CH₃CH₃

b. H₂C═O

c. CH₂Cl₂

1. CH₃N₂⁺
2. HNO₃
3. N₃^-
4. CH₃CONH₂
5. O₃

b. Draw a structure for each of the species that shows approximate bond angles.

c. Which species have no dipole moment?

Show the direction of the dipole moment in each of the following bonds (use the electronegativities given in [Table 1.3] ):

a. H3C—Br

b. H3C—Li

Which of the following has a bond closest to the ionic end of the bond spectrum?

CH₃NH₂ CH₃CH₃ CH₃F CH₃OH

Which of the following has a polar covalent bond?

CH₃NH₂ CH₃CH₃ CH₃F CH₃OH

Explain why HCl has a smaller dipole moment than HF, even though the H—Cl bond is longer than the H—F bond.

Which of the following has

a. the most polar bond?

b. the least polar bond?

NaI LiBr Cl₂ KCl

Which of the following molecules would you expect to have a dipole moment of zero?

g. BeCl₂

h. BF₃